Project institution: University of Glasgow
Project supervisor(s): Dr Andrei Shvarts (University of Glasgow), Dr Jingtao Lai (University of Glasgow), Prof Lukasz Kaczmarczyk (University of Glasgow) and Prof Todd Ehlers (University of Glasgow)
Overview and Background
Global climate and environmental change are increasingly resulting in weather extremes that impact society and infrastructure. These extremes include stormier climates with increased wind speeds, precipitation events or drought, and temperatures (amongst other things). A team of University of Glasgow researchers are developing an Earth systems digital twin for exascale computing that works on GPU computers and uses weather forecasts to predict the cascading effect of climate change events on environmental systems. Our goal is to provide predictions, at the national or large scale, of the impacts of environmental extremes on natural and urban settings. This project is one, stand alone, component of this larger scale project.
In this project, you will focus on the glacier-bedrock interface. Mountain glaciers are changing rapidly worldwide in response to climate change. Glacier changes affect global trends in freshwater availability, contribute to recent sea level changes, and affect regional water resources over the twenty-first century. However, uncertainties remain in projecting such impacts in future climate change scenarios. A major source of these uncertainties is the lack of understanding of glacier sliding – the relative motion between glacial ice and underlying rocks (Zoet, L. K., & Iverson, N. R., 2020). In this project, you will develop a GPU-accelerated multiscale modelling framework for glacier sliding to tackle this problem.
Your job while working on this project will involve software development for simulating the relevant multiphysical processes, applying the model to historic data for validation, working in a team/workgroup environment, attending regular research group seminars, integrating diverse environmental and satellite data into your software, and learning new techniques through ExaGEO training workshops.
Methodology and Objectives
Subglacial system consists of ice, water, and rocks. Among these components, different processes and feedbacks operate at different spatial and temporal scales, making it a challenging computational problem to simulate. To tackle this problem, this project will adopt a multiscale modelling approach combining microscale modelling of the ice-bedrock interface with macroscale simulation of glacier dynamics and subglacial hydrology. A particular focus will be developing models for GPU architectures to enable high-resolution and scalable simulation.
Methods used in this project will involve numerical simulation using the open-source parallel finite element library MoFEM developed and supported at the University of Glasgow (Kaczmarczyk, Ł., et al, 2020).
Teaser Project 1:
This teaser project, conducted during the first year, will focus on developing a microscale model of the contact interface between glacier ice and bedrock. When the ice is compressed by its own weight against the bedrock, the roughness of both the ice and bedrock surfaces creates a complex contact problem where only isolated regions of the interface are in actual contact. Simultaneously, the remaining areas form free volumes that can be occupied by flowing or stagnant (trapped) water mixed with sediments. The sub-project will build upon a previously developed finite-element framework (Shvarts, A.G. et al., 2021) by enabling its application in a distributed-memory parallel computing environment and providing further GPU acceleration using the functionality available in the MoFEM library. Additionally, the framework will be enhanced to incorporate friction between the ice and bedrock. Using available data to calibrate the model, the extended framework will predict the shear strength of the interface as a function of various parameters, including the weight of the ice, surface roughness, sediment density, and water pressure. These predictions will be compared with existing phenomenological models of glacial sliding to refine and improve the latter.
Teaser Project 2:
This sub-project, also conducted during the first year, addresses the macroscale problem and focuses on the behaviour of the glacier as a whole. It will leverage the finite-element model implemented in MoFEM, constructed using available topological and geological data. The model will incorporate the results from the microscale simulations of the first sub-project, which map ice properties to interfacial shear strength, to accurately inform the macroscopic interface behaviour. Utilizing parallel computing with GPU acceleration, this sub-project will simulate large-scale glacier dynamics under varying environmental conditions, including changes in ice thickness, surface temperature, and basal water pressure. These simulations will provide critical insights into the glacier’s flow patterns, deformation, and sliding behaviour, enabling predictions of its response to climate change scenarios. The outcomes will also help validate and refine existing phenomenological models, improving their applicability to real-world glacier systems.
References and Further Reading
- Zoet, L. K., & Iverson, N. R. (2020). A slip law for glaciers on deformable beds. Science, 368(6486), 76–78 (click here)
- Kaczmarczyk, Ł., et al, 2020. MoFEM: An open source, parallel finite element library. The Journal of Open Source Software, 5(45) (click here)
- Shvarts, A.G., Vignollet, J. and Yastrebov, V.A., 2021. Computational framework for monolithic coupling for thin fluid flow in contact interfaces. Computer Methods in Applied Mechanics and Engineering, 379, p.113738 (click here)
